Up to now, most of scholars work in geology and earthquake engineering considered that a very important Liujiapu fault （also named Kongjiaya fault） exists in Anning district of Lanzhou city, and maybe extends east to Sanyyuanxia across the main urban region of Lanzhou city. The fault was determined as a Holocene active fault, so it had seriously influence to the urban engineering and architectures. In recent study, through drilling at some sites along the fault lines in Anning district, especialy a large trenching study at Wenhua Jiayuan site in Anning district, we find that ＂Liujiapu fault＂ is just a interface between different terranes.